Sandwich structure with a high load-bearing capacity, as well as methods for the manufacture thereof

A method for manufacturing a sandwich structure comprising a thermoplastic core, which is arranged between two cover layers, in which the thermoplastic core is reinforced with fiber-reinforced thermoplastic reinforcing ribs, which extend between the cover layers, which method comprises the following steps:

• a) providing a composite panel, made of a thermoplastic core layer, which is connected to a fiber-reinforced layer, the fiber reinforced layer comprising a thermoplastic material and having at least one edge;
• b) folding at least one edge of at least the fiber-reinforced layer of the composite panel over a length which is at least equal to the thickness of the composite panel, so that a segment of the composite panel is obtained which is covered on at least two adjacent surfaces with the fiber-reinforced layer, the folding being performed using heat and pressure, wherein at least the fiber-reinforced layer is heated to a temperature higher than a glass-transition temperature of the thermoplastic material of the fiber-reinforced layer;
• c) repeating steps a) and b) at least once such that at least two segments of the composite panel are obtained;
• d) arranging at least two of the segments next to one another between two cover layers in such a manner that each of the at least two segments touches at least one of the two cover layers and such that the fiber-reinforced layer of at least one of the segments is positioned between the at least two segments and forms a fiber-reinforced thermoplastic reinforcing rib of the sandwich panel;
• and
• e) connecting the cover layers to the at least two segments to form the sandwich structure.